[cloudsymph]

hey there everyone.

i was just wondering if anyone knows why the beckmann rearrangement undergoes migration in an anti fashion?

and also if anyone could provide appropriate readings (articles, etc etc) for this topic it would be great also.  i'm writing an undergraduate lab report at the moment.  so i kind of need citations.

thanks in advance

cloudsymph

[kiwi]

hey there everyone.

i was just wondering if anyone knows why the beckmann rearrangement undergoes migration in an anti fashion?

and also if anyone could provide appropriate readings (articles, etc etc) for this topic it would be great also.  i'm writing an undergraduate lab report at the moment.  so i kind of need citations.

thanks in advance

cloudsymph

It's all to do with the mechanism of the reaction. The alkyl group anti to the leaving group is the one that migrates, due to 'stereoelectronic effects'. I'm not sure what level you're at, but more specifically because the alkyl group must approach the side of the nitrogen with the N-O antibonding orbital. There is a good explanation in Claydens Organic Chemistry.